The invention relates generally to a device for coupling two conduits to one another.
More particularly, the invention relates to a device for coupling a pipe, and especially a nipple, to a hose.
A known device for coupling a pipe to a hose includes a tubular coupling element having a first or front end which is received in the pipe and a second or rear end which is axially spaced from the front end. The coupling element is provided with elastic hooks which project radially outward from the rear end of the coupling element and extend toward the front end at a spacing from the outer periphery of the coupling element. The end of each hook remote from the rear end of the coupling element has a radially inward directed projection or nose which catches elastically behind a collar on the pipe. A first or front end portion of the hose extends into the coupling element via the rear end of the latter and bears tightly against the inner surface of the coupling element. The coupling element has an internal abutment and the front end portion of the hose is fed into the coupling element until the front end portion contacts the abutment. The hose is secured in the coupling element by means of a sleeve or retaining element having a first or rear end section which extends into the front end portion of the hose. The retaining element and the hose engage one another so as to form a seal between the same and the retaining element is fixed against withdrawal from the hose. The retaining element has a second or front end section which projects outward from the hose and has a larger diameter than the rear end section, and the front end section is provided with a radial surface which bears against a radial surface on the front end of the coupling element. A gap exists between the coupling element and the internal surface of the pipe and is sealed via a sealing ring which engages this internal surface.
A coupling device of the above type is disclosed in the commonly owned U.S. Pat. No. 4,708,375. The abutment for the front end portion of the hose is here constituted by a radially inward directed partition or wall of the coupling element. If the material of the abutment and the material at the end face of the hose do not form a bond with one another, which frequently occurs in an attempt to simplify assembly of the coupling element and the hose, there exists the possibility that the liquid, to be conveyed through the pipe and the hose will penetrate between the abutment and the end face of the hose. When the liquid is under pressure and the hose has a textile lining, there is then the danger that the liquid will penetrate into the textile lining axially from the end face of the hose, e.g., by capillary diffusion, so that the inner and outer layers of the hose are separated. This causes the hose to burst within a short time.